In the process of collecting parts for a new rig build-up and have some questions concerning the 203/205 doubler. This combo will be behind a c-6. I can get a c-6 with a 203 attached or can get a dodge 203. My thinking would be to go with the c-6/203 and get the adapters to mate a 205, but the person that has said parts said that he thought that the ford 203 shift levers would be in the way of the 205 shift levers. I'm in the dark on the matter on which combo would work the best and allow for the best install. Second question concerns if anybody besides NWF and ORD makes doubler adapters.

Thanks,
Brian

get the c6 and 203 - then buy a jeds kit and a junkyard 205



linky

http://www.jedsmachining.com/ford.html

The C6/203 combo sould work fine. I plan to go to the shorter 203 adapter on my next build. It will save a few inches of length over the 205 adapter. On mine the front driveshaft is close to the C6 pan with the 205 adapter, it will probably be even closer with the 203 adapter, but it sould be nothing major. Maybe look into a slightly smaller diameter shaft if need be.

As for the shifters, I did not use any of the 203 shifter. The shaft for the range box is not in the way of getting to the 205 shift rails, you will just need a simple linkage to get to it. Running the linkage for the rear shift rail can be tricky though, unless you decide to coin up for a prefabbed set up.

I personaly like some of the homebrewed cable linkage setups that have been discussed here on P4x4. I think it was in general discussion. I will probably be replacing my current shifters with that style next time around.

I got my doubler from Jed's through Stazworks...hard to beat it. I'd buy it again.

I have heard people mention the shorter adapter. School me on this.

I have heard people mention the shorter adapter. School me on this.

Well, there were two different adapters used to make up for the length between the 205 and the 203. I'm not sure about what was used with the newer cases like the 208. Anyway, the 203 is a good bit longer overall than the 205, so the adapter is shorter to keep them positioned about the same. Without measuring, i'd say it is about 6" give or take between the two.

The bolt pattern is the same, as is the spline of the transmission output shaft. You can swap t-cases all you want...BUT, you have to keep the adapter that was with the transmission because the output shaft is also different.

So, to go to the shorter adapter, the tranny would have to be torn down and reassembled with the shorter output.

Thanks for the reply. I noticed my 435/205 adapter was like 9" and my C6/205 adapter was much shorter. I was trying to shorten up my 435/203/205 combo but I guess it's not possible without altering the output. I'll just stretch the bronco wheelbase some more.:D

Thanks for the reply. I noticed my 435/205 adapter was like 9" and my C6/205 adapter was much shorter. I was trying to shorten up my 435/203/205 combo but I guess it's not possible without altering the output. I'll just stretch the bronco wheelbase some more.:D

I was in the same boat as you - I wanted a 435 /203/205 in my EB, but couldn't have the drivetrain be 25' long (not to mention that the 9" adapter just blew my mind!) Here is the shortest solution that I was able to come up with:

I have a very short (~1.1" thick) adapter that attaches to the back of the (4WD) NP435. The original 203 adapter (~0.75" thick) then bolts to back of the custom adapter. The NP203 can then be bolted to its adapter using the factory bolts and locations. In order to make all this work, the output on the NP435 did need to be cut/turned/resplined and the input on the GM 203 was swapped with a Dodge version (it is larger in diameter and does not require as much material to be removed from the 435 output before resplining).

The reason that the adapter needed to be 1.1" was so that there would be enough room (and some clearance) between the c-clip shoulder on the NP435 output and the snout of the NP203 input. There is just not enough room there to do it otherwise. The custom adapter uses the centering rings on the NP435 and the NP203 adapter for locating itself (making sure that the shafts are centered).

I had Jed's do the machine work for me - the pricing and turnaround was much better than I expected...


FWIW -

I had my stock 203 shaft resplined and had it case-hardened locally (along with my modified NP435 output shaft) - I figured that it was pretty-damn cheap insurance for $55.

For your reference, I had the shaft tested for hardness before and after having it case-hardened - it was ~45RC before and 62RC after (which is the same as the portion that hadn't been modified). Because the shafts are 8620, I did not have them annealed prior to case-hardening, nor did I have the non-modified portion of the shafts masked off - the entire shaft was case hardened.


-Chip

Thanks for all the info guys! Seems like the bronco crowd uses Jeds and the Chevy guys use ORD.